Sub Base for Infield Mixes?

I had a call late last week in regards to a project where infield mix will need to be installed over the winter season.  The question was, "The sub base will not meet compaction, can I undercut certain areas and fill with a granular backfill?"

To answer that question, the first step is to look at the base material.  Typically, and in this instance, a native soil material is used as the sub base.  The sub base needs to be at a minimum of 90% compaction.  In the winter season, 90% compaction is very difficult to achieve.  It it cannot be achieved, what are the options?

1. Undercut the areas that are not meeting compaction and backfill with like material stockpiled on site.
2. If compaction is still not achieved, imported backfill will need to be considered.  A backfill that is 1/4 inch minus is a good choice.  Why?  This material will pack tightly and also is not a large particle size.  This is important if the sub base is ever compromised during the tilling of the infield during standard preventative maintenance.  
3. If importing material is the approach, always undercut the entire infield sub base and compact before placing infield material.  This is important in the overall performance of the infield mix in both wet and dry conditions.

Go to j-dturf.com to learn more about J&D Turf.

Play on!

--Jamie

@JamieMehringer